He is a bit of a bonehead, there's no doubt about that, but he's also got talent which is something very few other Cavs have. He made half of his shots; he made 80% of his free throws, and maybe a higher percentage in clutch situations. He averaged over 9 rebounds. He's a pretty good interior passer. He can handle the ball. You'd have to rate his overall skill level as high.
The question is whether he'll learn how to play defense and cut down on his boneheaded plays (like his crazed attempt on a fast break to throw the ball off of the backboard and then dunk it, or his infamous flat on-the-back, over the head half-court pass to nowhere). I'm not sure he will, but given his talent I wouldn't rush to trade him for a draft pick.